Jurgen Klinsmann and Landon Donovan were already at odds before Klinsmann's tenure as U.S. national team head coach even began.

Not personally, mind you, but from an ideological standpoint, the two men could hardly be more different.

Klinsmann was appointed to shake up the American team, instilling his “24/7” brand of European-style play and almost as important, lifestyle. The former German national team striker and head coach wants his team to eat, sleep, breathe and live soccer, like players do in Europe. The implication being, of course, that that's not the case in the States.

For most of his career, Europe has been anathema to Donovan. His struggles to adapt during multiple stints in Germany are well documented, and though he enjoyed two successful brief loans with Everton, nearly all of his career club success has come in Major League Soccer.

Against this backdrop, Donovan missed eight of Klinsmann's first 10 games in charge of the national team, as club commitments, injury and illness all conspired to keep one of the team's best attacking options out of the lineup.

Still, Klinsmann played down rumors of a potential rift between the pair during a March 2012 interview with ESPN.

“There's no problem at all with Landon,” Klinsmann said. “It's for us way unfortunate that he wasn't available for the last eight games, whatever reason it was. We take it as it happened and are straightforward in our relationship, and obviously we want to see him back in the team.”

As Donovan returned to the national team last summer, his existentialist crisis began in full effect.

He wondered aloud if he'd reached the end of his line. Perhaps, he said, it was time to move on to the next phase in his life. Klinsmann sympathized, but also had some advice of his own.

“I had those moments, too,” Klinsmann said during a May 2012 teleconference. “They came usually when you were kind of ready for a next step or a change. It helped me a lot to change my environment, it kept me on my toes and I kept learning off the field a lot of things as well.”

Ready for a next step. A change of environment. This wasn't ambiguous. The Euro-centric coach was sending a clear message to his American-centric star.

Following the Galaxy's second straight MLS Cup win in December, Donovan did indeed take time away from the game, traveling to Asia among other places before finally returning to the Galaxy in late March, after he'd missed the USA's first three Hexagonal matches.

While he was away, Donovan went completely off the grid, much to the annoyance of his national team coach.

“We texted back and forth since the MLS Cup final,” Klinsmann said in an interview with Sports Illustrated in January. “I've offered lunches, dinners, coffee. But he wanted to take his break, and I said that's fine.”

Except, it probably wasn't fine.

“Jurgen and I have always been very open and honest with each other. It’s one thing I really respect the most about him,” Donovan said late last month upon his return to the Galaxy. “He certainly hasn’t agreed with a lot of my choices and that’s understandable.”

When he said Klinsmann hadn’t agreed with a lot of his choices, Donovan might have been referring to more than just his self-imposed sabbatical.

Though his worth to American soccer is unquestioned and he'll undoubtedly go down as one of the country's all-time greats, there has always been an element of “what if” to Donovan's career. By staying in Major League Soccer during his prime, Donovan has left a large portion of his greatness up to the imagination.

Klinsmann, Donovan's coach during a brief spell at Bayern Munich, hasn't shied away from his feelings on some American players' lack of ambition.

"The soccer environment within our American system is too easily content,” Klinsmann told the New York Times in January. “People give them too early the feeling of being content. So if it’s: 'I make it into MLS, I made it.' I always say, 'You haven’t made [expletive].'"

It's not difficult to imagine that message was aimed more at one player than any others.

Donovan is now back with the Galaxy and starting to round into form. There's little doubt the U.S. could still use a player of his quality, especially with its offense sputtering in recent games. Not surprisingly, though, Klinsmann doesn't seem to be in a big rush to welcome him back.

“There are players clearly ahead of Landon Donovan right now," Klinsmann said in a roundtable with reporters last week. "There is a chemistry being developed of a group and you have to feel where it is moving towards. He hasn't been part of the development of that team most of the time over the last two years, so chemistry is extremely important.”

Chemistry or no, it's hard to see a healthy, in-form Landon Donovan being passed up when the roster is announced for May and June's friendlies and World Cup qualifiers.

Whatever his performance is like with the national team though, Donovan's best chance of endearing himself to his coach may come after the 2013 MLS season is over, and his contract with the league expires.

Donovan has certainly made it in MLS but as we know, that sort of thing doesn't impress Jurgen Klinsmann very much.